Corner strip for wallboard construction



Nov. 5, 1963 J. A. COOPER 3,109,207

CORNER STRIP FOR WALLBOARD CONSTRUCTION Filed Nov. 50, 1960 INVENTOR.JACK A. COOPER United States Patent O 3,109,207 CORNER STRIP FORWALLBOARD CONSTRUCTION Jack A. (Pauper, 65 Valley View, San Rafael,Calif. Fried Nov. 30, 1960, Ser. No. 72,644 3 Claims. (CI. 20-92) Thisinvention relates to wallboard construction and especially to a cornerstrip for reinforcing the corner formed by two sheets of wallboard.

In wallboard construction the joint between adjacent sheets of wallboardwhich form a wall is usually covered by a paper tape extendinglengthwise of the joint. Said oining tape is made of paper and scarfedalong its edges to provide a smooth juncture between the paper and thewallboard to which it is secured. Joint cement is generally applied tothe margins of the wallboard sheets adjacent the joint in order toadhere the paper and additional joint cement is applied over the paper.to cover the same and provide a smooth uninterrupted surface. Such apractice is extremely effective on joints in the wall proper but cannotbe followed when two sheets of wallboard are used to form a corner.Since the corner is extremely vulnerable to injury, it is necessary toprovide reinforcement in addition to joining tape to project therelatively weak corner of the wallboard.

Heretofore several schemes have been proposed to protect wallboardcorners. Strips of metal bent to provide angles have been employed, inwhich case the legs of the angles are nailed or otherwise secured to theadjacent margins of the corner edge. In some cases the corners of suchangles are bullnosed to provide a smooth juncture.

Other prior art corner strips combine conventional joining tape withelongated fiat bars of steel, aluminum and other materials so that therigid metal bars overlie the edge of the corner to reinforce the same.In addition to the substantial expense of such prior art devices, animportant additional disadvantage resides in the fact that the operationof applying the reinforcing strip usually involves a procedure differentfrom that involved in the typical joining of two sheets of wallboard.

The main object of the present invention is the provision of aneffective corner strip for wallboard which is less expensive than priorart devices used for the same purpose.

Another object of the invention is the provision of a corner strip forreinforcing a wallboard corner joint and which strip may be applied insubstantially the same manner as conventional joining tape therebyeffecting a saving in the labor involved.

Still another object of the invention is the provision of a wallboardcorner strip which lends itself to manufacture by continuously operatingmachinery.

Other objects and advantages will be seen in the following specificationand the claims.

FIG. 1 is a perspective of a portion of a corner with the inventionapplied thereto and with portions broken away and in section.

FIG. 2 is a typical cross section through a corner joint showing thecompleted corner.

FIG. 3 is a side elevation, with portions broken away, of the cornerstrip of the invention, showing the same in a flat form.

FIG. 4 is a partial elevation and section showing the strip bent to theform in which it is merchandised and used.

In detail, and first with reference to FIG. 3, the invention comprises alength of conventional paper wallboard joining tape 1 which is scarfedalong its side edges as at 2, 3 to form feather edges so as to provide asmooth juncture between the tape and the wallboard to which it issecured.

3,1092%? Patented Nov. 5,1963

Centrally of the tape 1 and extending longitudinally thereof (FIG. 3) isa wire 4 which is preferably of steel and coated in any desired mannerto make the same rust proof. However the wire 4 may be of aluminum,plastic or any suitable material provided it is relatively rigid andcapable of withstanding the impacts to which a corner is usuallysubjected.

On the opposite side of wire 4 from tape 1 is a length of textilematerial, preferably cotton fabric, and indicated at 6. The thickness ofthe textile strip 6 is considerably greater than the thickness of papertape 1 so as to increase the thickness of the finished strip at thecentral portion of the same and at the same time protect the assembledstrip against breaking or tearing adjacent the wire 4. The strip 6 ispreferably somewhat narrower than tape 1.

Overlying the fabric 6 is a second length 8 of wallboard joining tapewhich may be about the same width as tape 6 but which is shown slightlywider so as to completely cover the fabric strip 6.

It will be understood that the assembly shown in FIG. 3 may be formedeconomically and at great speed by simultaneously unreeling the variouselements from reels, including the wire 4. At such assembly glue isapplied to the various parts so that a unitary strip is formed withpaper comprising the exterior sides. Preferably the additional step ofbending the finished strip to form an angle as shown in FIG. 4 is alsocarried out. However the strip may be merchandised in a flat conditionas shown in FIG. 3, if desired.

FIGS. 1 and 2 illustrate the manner in which the strip is used at atypical corner joint. In such a typical joint two sheets 10, 11 of wallboard are secured to stud 12 or whatever rough framing is involved. Inthe example shown a longitudinally extending edge 13 is formed by sheet10 and this edge 13 must be protected against injury. 1

The strip shown in FIG. 4 is applied to the corner so that the wire 4overlies the edge 13 thereby protecting it. Before the strip is applied,however, a thin layer of joint cement is applied to the margins ofwallboard so that the inner faces of tapes 1, 8 adhere to saidwallboard. Since the strip is in the form of an angle as shown in FIG.4, no skill is required to position the same so that the wire 4 isoverlying and protecting the edge 13. Additional joint cement is appliedat 14, 15 to provide a smooth juncture as shown in FIGS. 1 and 2.

It will be apparent that the steps involved in applying the strip aresubstantially the same as those involved in forming the joint betweenadjacent sheets of wallboard on a wall.

It will be noted that the fabric strip 6 gives additional body to thestrip adjacent the Wire where it is needed. There is no tendency for thestrip to tear or break adjacent the wire because of the presence of saidfabric strip. Despite the presence of the fabric material, the cornerstrip may be handled as if it were paper because the only exteriorsurfaces are paper. In this connection it will be understood that theadhesive which secures the various parts 1, 4, 6, 8 together ispreferably waterproof and dries hard and this would tend to make theassembled strip brittle were it not for the relatively thick fabric 6which contributes resiliency to the finished strip.

The resiliency provided by the fabric 6 is important in that itstrengthens the finished corner. If no resiliency were provided as bystrip 6, the finished corner would be vulnerable to impacts and would bemuch more likely to chip off. For the above reasons a strong cottondrill is preferred for fabric strip 6.

Another important feature of the above-described structure is that thewire 4 is completely encased in adhesive fabric and paper, and it isthus effectively protected against rust.

The specific description of the preferred form of the invention hereinset forth should not be taken as restrictive of the scope of theinvention as it will be apparent that various modifications in designmay be resorted to without departing from the scope of the followingclaims.

I claim:

1. In combination with a pair of vertical disposed wallboard sheets inabutment along vertical ends and connected together to form a unitarycorner having an exposed exterior edge at the intersection of the planesof the outer faces of said sheets; a corner strip reinforcing said edgecomprising:

a first elongated rectangular wallboard joining tape cementedsubstantially over its entire inner surface lengthwise along said cornerwith the central portion of said tape overlying said edge and with theside portions of said tape that are on opposite sides of said centralportion in covering relation respectively with the adjacent margins ofsaid corner,

a length of rigid wire coextensive in length with said tape in coveringrelation with said exposed edge and on the outer side of said firstelongated tape for protecting said edge against injury,

a second elongated rectangular wallboard joining tape overlying andsecured to said Wire and said first tape and cemented to said sheets.

2. Corner construction according to claim 1 wherein an elongated tape offabric is interposed between said Wire and said first tape andadherently secured to said first and second tapes.

3. In combination with a pair of vertically disposed wallboard sheets inabutment along vertical ends and connected together to form a unitarycorner having an exposed exterior edge at the intersection of the planesof the outer faces of said sheets; a corner strip reinforcing said edgecomprising:

a relatively narrow first length of rectangular wallboard joining tapecemented substantially over its entire inner surface lengthwise alongsaid corner with the central portion of said tape overlying said edge 4and with the side portions of said tape that are on opposite sides ofsaid central portion in covering relation respectively with the adjacentmargins of said corner,

a length of rectangular textile tape overlying said first tape along thecentral portion thereof,

a length of rigid wire overlying said textile tape and in coveringrelation with said exposed edge,

a relatively :wire second length of wallboar-d joining tape overlyingand secured to said wire and of sufficient width to cover said textiletape and said first joining tape and to provide a pair of marginalportions outwardly of said first tape and said textile tape,

said joining tapes and said textile tape being adherently securedtogether with said Wire interposed between said textile tape and saidsecond tape,

and said marginal portions of said second length being secured to saidcorner margins outwardly of said first tape by wallboard joint cement.

References Cited in the file of this patent UNITED STATES PATENTS902,563 Crowell Nov. 3, 1908 905,335 Lewis Dec. 1, 1908 1,285,465Tewksbury Nov. 19, 1918 1,358,283 Brown Nov. 9, 1920 1,474,699 WisbrockNov. 20, 1923 2,017,106 Sandell Oct. 15, 1935 2,126,833 Steinberger Aug.16, 1938 2,234,701 Lyman Mar. 11, 1941 2,590,846 Cuttings Apr. 1, 19522,593,859 Dunlap Apr. 2.2, 1952 2,636,835 Boulware Apr. 28, 19532,687,558 Dunlap Aug. 31, 1954 2,851,741 Stemples Sept. 16, 19582,862,264 Perna Dec. 2, 1958 2,904,856 Robinson Sept. 22, 1959 2,995,784Driscoll Aug. 15, 1961 FOREIGN PATENTS 693,160 Great Britain 1953 UNITEDSTATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,109,207November 5, 1963 Jack A, Cooper It is hereby certified that errorappears in the above numbered patent requiring correction and that thesaid Letters Patent should read as corrected below Column 4, line 9, for"wire" read wide Signed and sealed this 28th day of April 1964.

(SEAL) Attest:

ERNEST W. SWIDER EDWARD J. BRENNER Commissioner of Patents AttestingOfficer

1. IN COMBINATION WITH A PAIR OF VERTICAL DISPOSED WALLBOARD SHEETS INABUTMENT ALONG VERTICAL ENDS AND CONNECTED TOGETHER TO FORM A UNITARYCORNER HAVING AN EXPOSED EXTERIOR EDGE AT THE INTERSECTION OF THE PLANESOF THE OUTER FACES OF SAID SHEETS; A CORNER STRIP REINFORCING SAID EDGECOMPRISING: A FIRST ELONGATED RECTANGULAR WALLBOARD JOINING TAPECEMENTED SUBSTANTIALLY OVER ITS ENTIRE INNER SURFACE LENGTHWISE ALONGSAID CORNER WITH THE CENTRAL PORTION OF SAID TAPE OVERLYING SAID EDGEAND WITH THE SIDE PORTIONS OF SAID TAPE THAT ARE ON OPPOSITE SIDES OFSAID CENTRAL PORTION IN COVERING RELATION RESPECTIVELY WITH THE ADJACENTMARGINS OF SAID CORNER, A LENGTH OF RIGID WIRE COEXTENSIVE IN LENGTHWITH SAID TAPE IN COVERING RELATION WITH SAID EXPOSED EDGE AND ON THEOUTER SIDE OF SAID FIRST ELONGATED TAPE FOR PROTECTING SAID EDGE AGAINSTINJURY, A SECOND ELONGATED RECTANGULAR WALLBOARD JOINING TAPE OVERLYINGAND SECURED TO SAID WIRE AND SAID FIRST TAPE AND CEMENTED TO SAIDSHEETS.